System and method of exchanging identification information for mobile stations

ABSTRACT

A system is provided for allowing mobile stations to exchange identification information using a predetermined communication path for the purpose of obtaining identification information to use in establishing a different communication path for communicating.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/440,363 entitled “System And Method Of ExchangingIdentification Information For Mobile Stations,” which was filed on Jan.16, 2003. The entire disclosure of U.S. Provisional Application No.60/440,363 is hereby incorporated into the present application byreference.

BACKGROUND

[0002] 1. Field The systems and methods described in this patentdocument relate generally to wireless communication and morespecifically to identification information for mobile stations.

[0003] 2. Description of the Related Art

[0004] Mobile stations, such as mobile telephones, mobile email devices,and other mobile communication devices, which communicate via a wirelessnetwork, typically function as client devices that request access tovarious services through the wireless network. These services mayinclude telephone services, e-mail services, web access services andvarious messaging services. Wireless network operators require data frommobile stations to traverse gateways and central routing points, whichare located outside of the wireless network, to maintain strict billingand usage models. The primary goal of those running the networks is tomonitor data usage and charge appropriately, despite the fact that thismay limit the options for the mobile stations on the network. Thus,wireless users may be restricted in what they can do and may be forcedinto a limited data communication model that inhibits expansion of usagemodels. This restrictive network design limits the average revenue peruser and the growth of wireless networks for data traffic.

[0005] Systems for peer-to-peer communication are also available formobile stations. Current peer-to-peer communication systems, such as SMSor instant messaging, use centralized gateways that attempt to keeptrack of all users and correlate them into requested groups or buddylists. These systems force users to use centralized gateways for allcommunication, thus creating the potential for bottlenecks, dataslowdowns and single points of failure.

SUMMARY

[0006] A system is provided for allowing mobile stations to exchangeidentification information using a predetermined communication path forthe purpose of obtaining identification information to use inestablishing a different communication path for communicating.

[0007] According to some of the claims, provided is a method in a firstmobile station that comprises the following steps. In one step, thefirst mobile station exchanges network identification information with asecond mobile station using a wireless network and a service gateway. Inanother step, the first mobile station stores a network identificationcode of the second mobile station. In a third step, the first mobilestation requests that a wireless communication link be establishedbetween the first mobile station and the second mobile station via thewireless network using the network identification code wherein thecommunication link does not require any service gateway.

[0008] Also according to some of the claims, provided is a method in awireless network that comprises the following steps. In one step, thewireless network provides a first network identification code to a firstmobile station and a second network identification code to a secondmobile station. In another step, the wireless network transfers messagesbetween the first mobile station and the second mobile station via aservice gateway wherein the messages comprise the first networkidentification code, the second network identification code, or both. Ina third step, the wireless network provides a communication link betweenthe first mobile station and the second mobile station in response to arequest from either the first or second mobile stations or both thatincludes the first and second network identification codes wherein thecommunication link does not require any service gateway.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is a block diagram of a wireless communication system;

[0010]FIG. 2 is a block diagram of a system for exchanging mobilestation identification information through an email service;

[0011]FIG. 3 is a block diagram of a system for exchanging mobilestation identification information through an SMS service;

[0012]FIG. 4 is a block diagram of a system for exchanging mobilestation identification information through an SMS service and an IPaddress exchange service;

[0013]FIG. 5 is a block diagram of a system for exchanging mobilestation identification information through an IP address service;

[0014]FIG. 6 is a block diagram of a mobile station;

[0015]FIG. 7 is a flowchart of a method for exchanging mobile stationidentification information;

[0016]FIG. 8 is a flowchart of a method for receiving and acceptingidentification information from a mobile station, and

[0017]FIG. 9 is a block diagram of a dual-mode mobile communicationdevice.

DETAILED DESCRIPTION

[0018]FIG. 1 is a block diagram of an exemplary wireless communicationsystem. The system comprises a first mobile station 100, a second mobilestation 101, a wireless network 104, a first wireless network basestation 102, a second wireless network base station 103, and a servicegateway 106. The system is capable of connecting to various servicessuch as the Internet 108 via the service gateway 106.

[0019] In the example shown, each mobile station 100, 101 communicatesvia the wireless network base stations 102, 103 and the wireless network104, preferably using RF links which follow a radio protocol dictated bythe equipment in the wireless network 104. Other wireless communicationforms, however, may be used. The wireless network 104 preferably is anetwork such as GMS/GPRS, CDMANV-CDMA, EDGE, UMTS, or other compatiblenetwork. Each mobile station 100, 101 executes a sequence of connectionsteps so that a connection can be established with one of the wirelessnetwork base stations 102, 103. During the connection process, anidentification code such as an Internet Protocol (IP) address or someother code is assigned to the mobile station 100, 101. After receivingthe identification code, the mobile station 100 or 101 is able torequest services through the wireless network 104.

[0020] In this exemplary system, the service gateway 106 preferably isconnected to the wireless network 104 through documented TCP/IP orUDP/IP access points. When a request for service from a mobile station100, 101 is received by the service gateway 106, the service gateway 106functions as a proxy and sends the request to the Internet 108. In othersystem configurations, the service gateway 106 may alternatively proxyrequests to another wide-area network, a private network, a VPN, anintranet, or some other network arrangement. The connection from thedevice gateway 106 to the Internet 108 in this example is a networkconnection such as a high-speed private ISDN or frame relay link, butalternatively could be a low-speed public dial phone connection or someother type of connection.

[0021] In the exemplary wireless network 104, each mobile station 100,101 which attaches to the wireless network 104 requests a networkresource so that it can be addressed at a high layer, such as the IPlayer. In the exemplary systems of FIG. 1, each mobile station 100, 101is allocated a private, dynamic IP address each time it connects to thenetwork. The IP address might change each time a new connection is madeand the IP address resource is utilized. This IP address is maintainedwhile the user is actively using it, but may be unallocated if an idleperiod of non-use of sufficient duration occurs. This allows thewireless network 104 to manage the IP address resources and reduceinefficient use of these resources. Since the network 104 is private,only mobile stations 100, 101 and service gateways 106, which aredirectly attached to the wireless network 104, are able to use the IPaddresses assigned to each mobile station.

[0022]FIG. 2 is a block diagram of an exemplary system for exchangingmobile station identification information through an email service. Thesystem comprises a first mobile station 200, a second mobile station201, a wireless network 204, a first wireless network base station 202,and a second wireless network base station 203, which in this examplecorrespond to similar elements described with respect to FIG. 1. Thesystem further comprises an email gateway 206 for connecting with anemail service 208.

[0023] The mobile stations 200, 201 exchange identification informationusing a predetermined communication path so that they can obtain theidentification information to use in establishing a different andpreferably better communication path. In this example, the first mobilestation 200 sends its currently assigned IP address to the second mobilestation 201 via an email message 210 which is addressed to the secondmobile station 201. Preferably, an IP-Monitoring agent running in thefirst mobile station 200 automatically transmits the email message 210.The email message optionally could contain, in addition to the currentlyassigned IP address, status information regarding the user, locationinformation regarding the user, and/or information relating to thecapabilities of the mobile station such as device type and/or supportedfeatures and communication methods. The status information may includeavailability information that indicates how long the user is availableor unavailable or some other relevant information. The locationinformation may include the user's current base station location,country code and/or time zone.

[0024] The exemplary system operates in accordance with the followingdescription. An IP-monitoring agent in the first mobile station 200monitors and detects when the IP address of the first mobile station 200changes, preferably, by monitoring memory in the first mobile station200. When the IP-monitoring agent detects that the IP address haschanged, it sends an e-mail message 210 to other mobile stations thatare registered as associates of the user of the first mobile station200. An associate could be a friend, an instant-messaging buddy, aperson within a specified workgroup, or a co-worker of the user. Theregistration of associates may be recorded in a mapping table thatpreferably resides in the mobile station, but that also could reside inan external location. The mapping table indicates which mobile stationsshould be notified when the IP address of the first mobile station 200changes. The mapping table preferably includes the email addresses ofassociates, which are used in the email message as the recipientaddresses. Alternatively, the user of the first mobile station 200 maysend the email message 210 manually. Also, the first mobile station 200may send its IP address to the second mobile station 201 in an unrelatedemail message that was sent for another purpose. After a second mobilestation receives the email message, it preferably sends a response tothe first mobile station 201 that preferably confirms the second mobilestation's reception of the email message and optionally provides updatedinformation, such as status information and availability informationregarding the second mobile station. The response may be in the form ofa reply email message or in some other form.

[0025] The e-mail service 208 preferably is a publicly available servicesuch as Hotmail, a service provided by an ISP such as AOL, or acorporate service such as a Microsoft Exchange server. The email gateway206 is an example of a service gateway 106 (FIG. 1), which allows themobile stations 200, 201 to send and receive email messages using theemail service 208.

[0026] The mobile stations 200, 201 use the identification informationsuch as IP addresses to establish a communication link 212 within thewireless network 204 that does not utilize resources outside of thewireless network 204. Because the communication link 212 between themobile stations 200, 201 does not traverse a service gateway, using thecommunication link 212 should reduce latency and reduce overall networktraffic. In addition, the communication link 212 can be used to exchangemessages which are arbitrarily large, which is an improvement over the160-character limit of current short message service (SMS) services.

[0027] The communication links 212 can act as the foundation for acollection of wireless network-only services that do not rely uponexternal gateways. These services include a range of peer-to-peer orclient-server services. For example, an instant messaging conversationcan take place between two or more peers in a collaborative group, orthe first mobile station 200 could act as a web server and allow thesecond mobile station 201 to attach using HTTP protocols to provide webpages for information exchange. Other wireless network-only services arealso possible.

[0028] The system described with respect to FIG. 2 allows mobilestations 200, 201 to be aware of and use IP addresses of other mobilestations which communicate via the wireless network 204 even when the IPaddresses of the mobile stations change. IP addresses for mobilestations can change when the wireless network 204 uses a dynamic IPaddress mechanism such as DHCP.

[0029]FIG. 3 is a block diagram of a system for exchanging mobilestation identification information through an SMS service. The systemcomprises a first mobile station 300, a second mobile station 301, and awireless network 304 that further comprises a first wireless networkbase station 302 and a second wireless network base station 303. Thesystem further comprises an SMS service center 306.

[0030] The wireless network 304 provides the mobile stations 300, 301with support for a short messaging service (SMS). The service providerfor this service is the SMS service center 306 (SMSC), which acts as theservice gateway which supports the routing of messages between mobilestations 300 and 301. The SMSC 306 may also support routing of messagesto and from senders which are not connected to the wireless network 304.

[0031] In this example, the current IP address of the first mobilestation 300 is sent in an SMS message 310 which is addressed to thesecond mobile station 301. The SMS message 310 preferably is sentautomatically by an IP-Monitoring agent running within the first mobilestation 300. Alternatively, the SMS message 310 may be sent manually bythe user of the first mobile station 300 or the IP address may be sentto the second mobile station 301 in a message that was sent for anotherpurpose.

[0032] Once the second mobile station 301 has received an SMS message310 containing identification information for the first mobile station300, the current IP address associated with the first mobile station 300is known to the second mobile station 301, which can send data to thefirst mobile station 300. Also, after the second mobile station 301provides its identification information to the first mobile station 300,the current IP address associated with the second mobile station 301 isknown to the first mobile station 300, which can send data to the secondstation 301. The two mobile stations 300, 301 are thus able tocommunicate directly using a communication link 312 that only useswireless network 304 resources. This communication link 312 can reducelatency, reduce overall network traffic and allow for larger messages tobe exchanged beyond the 160-character limit of SMS. After an SMS message310 is sent that contains identification information, the receivingmobile station preferably sends a response that confirms the receptionand returns any updated information such as status information andavailability information regarding the receiving mobile station.

[0033]FIG. 4 is a block diagram of a system for exchanging mobilestation identification information through an SMS service and an IPaddress exchange service. The system comprises a first mobile station400, a second mobile station 401 and a wireless network 404, whichfurther comprises a first wireless network base station 402 and a secondwireless network base station 403. The system further comprises an SMSservice center 406 and an IP address exchange service 408.

[0034] The mobile stations 400, 401 can exchange IP addresses using SMSmessages 410 and can establish a communication link 412 that only usesthe resources of the wireless network 404 in a manner consistent withthe system described with reference to FIG. 3. The IP address exchangeservice 408 in this example also processes the SMS messages 410 toprovide additional services for the mobile stations 400, 401. The IPaddress exchange service 408 is capable of keeping track of andpublishing identification information for mobile stations 400, 401, aswell as location and presence information, for other mobile stations.

[0035]FIG. 5 is a block diagram of a system for exchanging mobilestation identification information through an IP address service. Thesystem comprises a first mobile station 500, a second mobile station501, and a wireless network 504 that further comprises a first wirelessnetwork base station 502 and a second wireless network base station 503.The system further comprises an Internet gateway 506 for providing aconnection to the Internet 507 and an IP address service 508 that isaccessible via the Internet. The Internet gateway 506 preferablyprovides TCP/IP proxy agents that allow the mobile stations 500, 501 toaccess a wide range of services offered by sites on the Internet 507,including the IP address service 508. In this example, the HTTP protocolis used to exchange identification information between the mobilestations 500, 501, via the IP address service 508, in order to establisha communication link 512.

[0036] The IP address service 508 preferably is a web service that ishosted by a web server. Alternatively, the IP address service 508 may bea web application hosted by a web server or by an application server. Ina preferred mode of operation, the first mobile station 500 uploads HTTPpackets 510 that contain the IP address associated with the first mobilestation 500 to the IP address service 508. The second mobile station 501then uses the HTTP protocol to download HTTP packets 511 that containthe IP address associated with the first mobile station 500. Similarly,the second mobile station 501 uploads HTTP packets 510 that contain theIP address associated with the second mobile station 501 to the IPaddress service 508. The first mobile station 500 then uses the HTTPprotocol to download HTTP packets 511 that contain the IP addressassociated with the second mobile station 501. Each mobile station 500,501 can then use the IP addresses obtained as described above toestablish and communicate directly over a communication link 512 whichuses only the resources of the wireless network 504.

[0037] To receive identification information for other mobile stations,preferably the mobile stations 500, 501 periodically poll the IP addressservice 508 to determine whether IP addresses for other mobile stationshave changed. Alternatively, the IP address service 508 may notify themobile stations 500, 501 when an IP address has changed. Thenotification preferably occurs directly over the wireless network 504.Alternatively, the notification may use another service such as an emailmessage, an SMS message, or a circuit-switched telephone call.

[0038] In another exemplary system, a mobile station can use a pluralityof different services to obtain identification information. In thisexample, the mobile station may use the email service when exchangingidentification information with a second mobile station, use a SMSservice when exchanging information with a third mobile station, use anIP address exchange service to exchange identification information witha fourth mobile station, or use an IP address service to exchangeidentification or information with a fifth mobile station. Also, it ispossible that one or more of these data exchange systems does not work.Therefore, as the mobile station 200, 300, 400, 500 tries each systemand gets a failure, or in the absence of a return acknowledgment, itwould use other systems and continue sending the updated IP addressinformation message. For example, if the message is sent using the SMSsystem and no acknowledgment is received after a pre-determined periodof time, the message is sent using the email system. If the emailacknowledgment message is not received after the pre-determined periodof time, the method is sent using the HTTP system. The system ensuresthat each correspondent is updated with the current IP address and thateach message sent receives an acknowledgment.

[0039]FIG. 6 is a block diagram of an exemplary mobile station 612. Theexemplary mobile station 612 comprises a wireless transceiver 600 forcommunicating with a wireless network, a user interface 602 forcommunicating with a user and a memory module 606 for storing andretrieving information such as an IP address mapping table 608 and an IPaddress 609. The mobile station 612 further comprises an IP addressapplication 604.

[0040] The IP address application 604 monitors the IP address 609 thatis stored in the memory module 606 of the mobile station. The IP address609 is specific to the mobile station and is assigned by the wirelessnetwork. Preferably, when the IP address 609 changes, the IP addressapplication 604 sends a message to the mobile stations listed in the IPaddress mapping table 608. The message contains the newly updated IPaddress 609, and can be sent using one of the earlier described systems.The addresses for the recipients of the message are preferably retrievedfrom an address book stored on the mobile station. Alternatively, therecipient address information may be retrieved from the IP addressmapping table 608 or the recipient address information may be manuallyentered by the user of the mobile station 500.

[0041] The exemplary IP address mapping table 608 containsidentification information for mobile stations with which the user ofthe mobile station wishes to communicate. For each such mobile station,the identification information preferably includes the name of the userthe mobile station, the current IP address of the mobile station, andthe previous IP address of the mobile station.

[0042] The current IP address of a mobile station is updated in the IPaddress mapping table 608 when an identification message is receivedthat specifies a new IP address. In this example, the message istransmitted through the wireless network and received by the wirelesstransceiver 600. The message is displayed on a display screen includedin the user interface 602 by a message application (not shown). Themessage application displays a listing of events to the user via theuser interface 602. The listing is preferably sorted chronologically andmay include incoming and outgoing email messages, incoming and outgoingtelephone calls, incoming and outgoing SMS messages, task reminders,and/or IP address update messages. The IP address update messagepreferably contains a unique string in a subject field of the messagethat indicates the type of the message. Alternatively, the IP addressupdate message may contain a unique string or binary-encoded elementelsewhere in the message that indicates the type of the message.Preferably, the new IP information and base station location is hiddenfrom the user. There are typically fields within email messages andwithin SMS messages that can be used for this purpose. For example,within an SMS message a user data header field that is not normallydisplayed to a user can be used.

[0043] Once the identification message is processed by the mobilestation 612, the user of the mobile station 612 can later decide to usethe identification information (e.g. IP information) to initiate apeer-to-peer conversation. Since the user is in a group list orpreferred correspondents list, the initiator simply needs to send afirst invitation to chat message. This first invitation message acts asboth a request and an introduction as to why a conversation is desired.The recipient of the invitation message might then either have theirdevice set to quiet or busy mode so that the invitation is automaticallyrejected with a busy indication returned as a reason for a rejection ofthe invitation. Alternatively, the recipient might read the message anddecide that it cannot deal with the issue at that moment and reject themessage or the user might accept the message and send back a chatacceptance indication as a response. After a chat acceptance indicationis returned, a communication session can begin.

[0044] In this example, when the IP address application 604 detects thatan IP address update message has been received by the mobile station,the IP address application 604 extracts the IP address from the IPaddress update message and updates the corresponding information in theIP address mapping table 608. The previous IP address for the mobilestation that sent the IP address update message is preferably retainedin the IP address mapping table 608. The previous IP address can beretained to allow returned messages addressed to the new address to beresent to the old address in case the updating of the IP address shouldnot have occurred.

[0045] Preferably, messages sent using the exemplary system describedherein are encrypted by the sending mobile station, so that when amessage is sent to an unintended recipient mobile station, the recipientmobile station cannot read the message. Known public or private keyencryption systems exist that can be used so that only the intendedrecipient mobile station can decrypt the message. A message may be sentto an unintended recipient mobile station, for example, when the IPaddress for an intended recipient mobile station stored in the IPaddress mapping table 608 has been reassigned to a different mobilestation, and the new IP address for the intended recipient mobilestation has not yet been received by the sending mobile station.

[0046]FIG. 7 is a flowchart that illustrates an exemplary process foruse by a primary mobile station for exchanging mobile stationidentification information with correspondent mobile stations. Thisprocess illustrates how two mobile station can exchange identificationcodes such as IP addresses so that a communication link can beestablished between the two mobile stations over the wireless networkusing the IP addresses.

[0047] The process begins at step 700, where a mobile station (MS)detects that it has been assigned a new address by the wireless network.This detection could occur through the use of radio interface code inthe MS since, preferably, radio interface code is used to re-negotiatenetwork parameters for resource allocation. The new address is passedthrough the MS to the application layer where a module such as the IPaddress application 604 detects the new address. This address could bean IPv4 address, an IPv6 address or some other network address used by awireless network. At step 702, the new address is stored so that futurechanges can be easily detected. After the address is stored at step 704,the MS preferably through the software locates the affectedcorrespondents and determines the method it will use to send an IPaddress update message to the affected correspondents. After identifyingthe delivery method, the primary MS, at step 706, transmits the newmobile station IP address to the correspondent mobile stations in the IPaddress update message. The IP address update message is transmitted viaa wireless network and a service gateway preferably as an email message,an SMS message, or using the HTTP protocol.

[0048] After transmitting IP update messages, the primary MS, at step708, sets a timer and waits for the reception of an acknowledgmentmessage. An exemplary method for sending acknowledgments (A) isillustrated in FIG. 8. If an acknowledgment message is not receivedbefore the timer expires, preferably the MS will attempt to transmit theIP address update message using another method. If no other methods fortransmitting the update message is available, the process ends at step716. But, if there are other available methods for sending an updatemessage, then another method is selected at step 714. After the nextmethod is selected, the IP address update message is sent using thisnext method. At step 708, the timer is set again and the MS waits for anacknowledgment.

[0049] Alternatively, instead of proceeding to step 712, the MS couldtry re-transmitting the IP update message using the same transmissionmethod. The MS could attempt to re-send the update message a number oftimes before abandoning on that transmission method. After abandoning onthat transmission method, the MS could proceed to step 712.

[0050] As a further alternative, two or more methods of sending theaddress update message could be attempted simultaneously. The firstsuccessful message would be acknowledged, thus reducing latency byassuring that the fastest of multiple methods is used.

[0051] When an acknowledgment is received from a correspondent MS, theprimary MS saves any information received in the acknowledgment messageat step 720.

[0052] When a peer-to-peer conversation is desired, either the primaryMS or a correspondent MS can initiate a direct peer-to-peer connection(presuming both the primary and correspondent mobile stations haveprovided current identification codes to the other). A user at theprimary MS, for example, can compose a peer-to-peer message and send itwithout having to send an explicit invitation or wait for presenceinformation. The MS then waits for a response, a timeout or a rejectionfrom the correspondent (step 722). If no response is received in apredetermined time period or if the correspondent sends a reject messageback, the connection is terminated and the peer-to-peer conversation isabandoned 724. For example, the correspondent might see the message andsend back an “I am currently busy” indication to tell the sender that apeer-to-peer conversation is currently not possible. However, if thecorrespondent sends a response message back, it is assumed that apeer-to-peer conversation is open and a full peer-to-peer communicationlink is opened (step 726).

[0053]FIG. 8 is a flowchart that illustrates a process for receiving andaccepting identification information from a mobile station. The processstarts at step 800 where the MS monitors incoming communications. Whenan incoming message is received, the MS first determines if the incomingmessage is an incoming email, SMS or HTTP-based message (step 802). Inmost wireless networks it is now possible for Wireless Access Protocol(WAP) gateways to push HTTP messages to mobile stations. If the incomingmessage is not one of those types, the MS determines if the incomingmessage is a peer-to-peer message from a correspondent that has notestablished a full peer-to-peer communications link such as aninvitation to chat message (step 804). If the incoming message is notthat type of message, the incoming message is processed in accordancewith procedures designed for other types of messages (step 806). Forexample, the incoming message could be a peer-to-peer communication withan existing correspondent or an acknowledgment message from an addressupdate message (A).

[0054] If the incoming message is an email, SMS or HTTP message then theMS determines if the incoming message is an address update message atstep 808. Preferably, the MS makes this determination by examining aparticular field of the message and identifying a unique identifier,tag, string or some other predetermined pattern. If the MS determinesthat the incoming message is not an address update message, then themessage is processed as normal (step 810). If the MS determines that theincoming message is an address update message, the MS then determineswhether the incoming message is from a known correspondent at step 812.

[0055] The MS is preferably configured such that a user can designatecertain correspondent addresses as preferred or non-preferred. The MScan use the designations when determining how to respond to message. Forexample, if an address update request is received from a non-preferredcorrespondent, the MS may automatically reject the message or prompt theuser to accept or reject the message. This check provides for some levelof privacy and ensures that each person involved in peer-to-peercommunications has agreed to such communications. If a person requestinga peer-to-peer communication is unknown or is not considered a preferredpeer-to-peer correspondent, a message can be returned that communicatesthat the address update message was rejected. If the message isaccepted, the correspondent's entry in the address book database orRAM-based file is updated with the new IP address. This mapping tableprovides the basis for setting up and accepting peer-to-peercommunications. The mapping table for each mobile station can thereforebe specific for a user and only contain identification addresses forcorrespondents chosen by the user.

[0056] If the message was not a normal email, SMS or HTTP message butwas an invitation to chat message, the MS determines if it has been setby the user to a busy or reject mode such as quiet mode (step 820). Aninvitation is regarded as a message from a preferred correspondent thatcurrently does not have a fully established peer-to-peer communicationpending. Quiet mode is typically a do-not-disturb mode or busy modewhere all chat requests are rejected. If the mobile station has been setto automatically reject chat requests, a message is immediately sentback with the appropriate code (step 822). If a peer-to-peer message isreceived from a correspondent that is not preferred, the user will havethe option of accepting or rejecting the communication, oralternatively, the message may be automatically rejected. Otherwise, theuser is informed of the incoming chat request and can reject or acceptthe invitation to chat (step 824). If the user rejects the invitation,the user may optionally provide a reason, and the rejection message istransmitted to the originator of the request 826. Otherwise, the usercan enter a response message that functions as an acceptance of thepeer-to-peer communication request (step 828).

[0057] Once established, the communication link routes peer-to-peermessages between the mobile stations, preferably using only theresources of the wireless network without using external servicegateways. When messages to and from the mobile stations do not traverseservice gateways, overall network traffic can be reduced and thedelivery time of the messages can be reduced. Also, size restrictionsare not imposed on the messages by services or gateways since they arenot used.

[0058] An example usage of the communication link is a chat sessionwhere messages are exchanged in real time between the users of themobile stations, as described above. Many other usages for thecommunication link are possible. A method of exchanging mobile stationidentification information may include additional or fewer steps thanthose illustrated in FIGS. 7 and 8.

[0059] Shown in FIG. 9 is a block diagram of an exemplary dual-modemobile communication device. The dual-mode communication device isanother example of a possible mobile station.

[0060] The exemplary dual-mode mobile communication device 910 includesa transceiver 911, a microprocessor 938, a display 922, Flash memory924, RAM memory 926, auxiliary input/output (I/O) devices 928, a serialport 930, a keyboard 932, a speaker 934, a microphone 936, a short-rangewireless communications sub-system 940, and may also include otherdevice sub-systems 942. The transceiver 911 preferably includes transmitand receive antennas 916, 918, a receiver 912, a transmitter 914, one ormore local oscillators 913, and a digital signal processor 920. Withinthe Flash memory 924, the dual-mode mobile communication device 910preferably includes a plurality of software modules 924A-924N that canbe executed by the microprocessor 938 (and/or the DSP 920), including avoice communication module 924A, a data communication module 924B, and aplurality of other operational modules 924N for carrying out a pluralityof other functions.

[0061] The dual-mode mobile communication device 910 is preferably atwo-way communication device having voice and data communicationcapabilities. Thus, for example, the dual-mode mobile communicationdevice 910 may communicate over a voice network, such as any of theanalog or digital cellular networks, and may also communicate over adata network. The voice and data networks are depicted in FIG. 9 by thecommunication tower 919. These voice and data networks may be separatecommunication networks using separate infrastructure, such as basestations, network controllers, etc., or they may be integrated into asingle wireless network.

[0062] The communication subsystem 911 is used to communicate with thevoice and data network 919, and includes the receiver 912, thetransmitter 914, the one or more local oscillators 913 and may alsoinclude the DSP 920. The DSP 920 is used to send and receive signals toand from the transmitter 914 and receiver 912, and is also utilized toreceive control information from the transmitter 914 and to providecontrol information to the receiver 912. If the voice and datacommunications occur at a single frequency, or closely-spaced set offrequencies, then a single local oscillator 913 may be used inconjunction with the transmitter 914 and receiver 912. Alternatively, ifdifferent frequencies are utilized for voice communications versus datacommunications, then a plurality of local oscillators 913 can be used togenerate a plurality of frequencies corresponding to the voice and datanetworks 919. Although two antennas 916, 918 are depicted in FIG. 9, thedual-mode mobile communication device 910 could be used with a singleantenna structure. Information, which includes both voice and datainformation, is communicated to and from the communication module 911via a link between the DSP 920 and the microprocessor 938. The detaileddesign of the communication subsystem 911, such as frequency band,component selection, power level, etc., is dependent upon thecommunication network 919 in which the dual-mode mobile communicationdevice 910 is intended to operate. For example, a dual-mode mobilecommunication device 910 intended to operate in a North American marketmay include a communication subsystem 911 designed to operate with theMobitex™ or DataTAC™ Mobile data communication networks and alsodesigned to operate with any of a variety of voice communicationnetworks, such as AMPS, TDMA, CDMA, PCS, etc., whereas a device 910intended for use in Europe may be configured to operate with the GeneralPacket Radio Service (GPRS) data communication network and the GSM voicecommunication network. Other types of data and voice networks, bothseparate and integrated, may also be utilized with the dual-mode mobilecommunication device 910.

[0063] Depending upon the type of network or networks 919, the accessrequirements for the dual-mode mobile communication device 910 may alsovary. For example, in the Mobitex and DataTAC data networks, mobiledevices are registered on the network using a unique identificationnumber associated with each device. In GPRS data networks, however,network access is associated with a subscriber or user of a mobiledevice. A GPRS device typically requires a subscriber identity module(“SIM”), which is required in order to operate a dual-mode mobilecommunication device on a GPRS network. Local or non-networkcommunication functions (if any) may be operable, without the SIM, but adual-mode mobile communication device will be unable to carry out anyfunctions involving communications over the data network 919, other thanany legally required operations, such as 911 emergency calling.

[0064] After any required network registration or activation procedureshave been completed, the dual-mode mobile communication device 910 maythen send and receive communication signals, including both voice anddata signals, over the network 919 (or networks). Signals received bythe antenna 916 from the communication network 919 are routed to thereceiver 912, which provides for signal amplification, frequency downconversion, filtering, channel selection, etc., and may also provideanalog to digital conversion. Analog to digital conversion of thereceived signal allows more complex communication functions, such asdigital demodulation and decoding to be performed using the DSP 920. Ina similar manner, signals to be transmitted to the network 919 areprocessed, including modulation and encoding, for example, by the DSP920 and are then provided to the transmitter 914 for digital to analogconversion, frequency up conversion, filtering, amplification andtransmission to the communication network 919 (or networks) via theantenna 918. Although a single transceiver 911 is shown in FIG. 9 forboth voice and data communications, it is possible that the dual-modemobile communication device 910 may include two distinct transceivers, afirst transceiver for transmitting and receiving voice signals, and asecond transceiver for transmitting and receiving data signals.

[0065] In addition to processing the communication signals, the DSP 920also provides for receiver and transmitter control. For example, thegain levels applied to communication signals in the receiver 912 andtransmitter 914 may be adaptively controlled through automatic gaincontrol algorithms implemented in the DSP 920. Other transceiver controlalgorithms could also be implemented in the DSP 920 in order to providemore sophisticated control of the transceiver 911.

[0066] The microprocessor 938 preferably manages and controls theoverall operation of the dual-mode mobile communication device 910. Manytypes of microprocessors or microcontrollers could be used here, or,alternatively, a single DSP 920 could be used to carry out the functionsof the microprocessor 938. Low-level communication functions, includingat least data and voice communications, are performed through the DSP920 in the transceiver 911. Other, high-level communicationapplications, such as a voice communication application 924A, and a datacommunication application 924B may be stored in the Flash memory 924 forexecution by the microprocessor 938. For example, the voicecommunication module 924A may provide a high-level user interfaceoperable to transmit and receive voice calls between the dual-modemobile communication device 910 and a plurality of other voice devicesvia the network 919. Similarly, the data communication module 924B mayprovide a high-level user interface operable for sending and receivingdata, such as e-mail messages, files, organizer information, short textmessages, etc., between the dual-mode mobile communication device 910and a plurality of other data devices via the network 919. In thedual-mode mobile communication device 910, an IP address application, asdescribed above, may also be implemented as a software module orapplication, or incorporated into one of the software modules 924A-924N.

[0067] The microprocessor 938 also interacts with other dual-mode mobilecommunication device subsystems, such as the display 922, Flash memory924, random access memory (RAM) 926, auxiliary input/output (I/O)subsystems 928, serial port 930, keyboard 932, speaker 934, microphone936, a short-range communications subsystem 940 and any other dual-modemobile communication device subsystems generally designated as 942.

[0068] Some of the subsystems shown in FIG. 9 performcommunication-related functions, whereas other subsystems may provideresident or on-device functions. Notably, some subsystems, such askeyboard 932 and display 922 may be used for both communication-relatedfunctions, such as entering a text message for transmission over a datacommunication network, and device-resident functions such as acalculator or task list or other PDA type functions.

[0069] Operating system software used by the microprocessor 938 ispreferably stored in a persistent store such as Flash memory 924. Inaddition to the operating system, which controls all of the low-levelfunctions of the dual-mode mobile communication device 910, the Flashmemory 924 may include a plurality of high-level software applicationprograms, or modules, such as a voice communication module 924A, a datacommunication module 924B, an organizer module (not shown), or any othertype of software module 924N. The Flash memory 924 also may include afile system for storing data. These modules are executed by themicroprocessor 938 and provide a high-level interface between a user ofthe dual-mode mobile communication device and the mobile device. Thisinterface typically includes a graphical component provided through thedisplay 922, and an input/output component provided through theauxiliary I/O 928, keyboard 932, speaker 934, and microphone 936. Theoperating system, specific dual-mode mobile communication devicesoftware applications or modules, or parts thereof, may be temporarilyloaded into a volatile store, such as RAM 926 for faster operation.Moreover, received communication signals may also be temporarily storedto RAM 926, before permanently writing them to a file system located inthe persistent store 924.

[0070] An exemplary application module 924N that may be loaded onto thedual-mode mobile communication device 910 is a personal informationmanager (PIM) application providing PDA functionality, such as calendarevents, appointments, and task items. This module 924N may also interactwith the voice communication module 924A for managing phone calls, voicemails, etc., and may also interact with the data communication modulefor managing e-mail communications and other data transmissions.Alternatively, all of the functionality of the voice communicationmodule 924A and the data communication module 924B may be integratedinto the PIM module.

[0071] The Flash memory 924 preferably provides a file system tofacilitate storage of PIM data items on the dual-mode mobilecommunication device 910. The PIM application preferably includes theability to send and receive data items, either by itself, or inconjunction with the voice and data communication modules 924A, 924B,via the wireless network 919. The PIM data items are preferablyseamlessly integrated, synchronized and updated, via the wirelessnetwork 919, with a corresponding set of data items stored or associatedwith a host computer system, thereby creating a mirrored system for dataitems associated with a particular user. The Flash memory 924 alsocontains an IP address associated with the dual-mode mobilecommunication device 910, and an IP address mapping table, as describedabove.

[0072] The dual-mode mobile communication device 910 may also bemanually synchronized with a host system by placing the dual-mode mobilecommunication device 910 in an interface cradle, which couples theserial port 930 of the dual-mode mobile communication device 910 to theserial port of the host system. The serial port 930 may also be used toenable a user to set preferences through an external device or softwareapplication, or to download other application modules 924N forinstallation. This wired download path may be used to load an encryptionkey onto the dual-mode mobile communication device 910, which is a moresecure method than exchanging encryption information via the wirelessnetwork 919.

[0073] Additional application modules 924N may be loaded onto thedual-mode mobile communication device 910 through the network 919,through an auxiliary I/O subsystem 928, through the serial port 930,through the short-range communications subsystem 940, or through anyother suitable subsystem 942, and installed by a user in the Flashmemory 924 or RAM 926. Such flexibility in application installationincreases the functionality of the dual-mode mobile communication device910 and may provide enhanced on-device functions, communication-relatedfunctions, or both. For example, secure communication applications mayenable electronic commerce functions and other such financialtransactions to be performed using the dual-mode mobile communicationdevice 910.

[0074] When the dual-mode device 910 is operating in a datacommunication mode, a received signal, such as a text message or a webpage download, will be processed by the transceiver 911 and provided tothe microprocessor 938, which will preferably further process thereceived signal for output to the display 922, or, alternatively, to anauxiliary I/O device 928. A user of the dual-mode mobile communicationdevice 910 may also compose data items, such as email messages, usingthe keyboard 932, which is preferably a complete alphanumeric keyboardlaid out in the QWERTY style, although other styles of completealphanumeric keyboards such as the known DVORAK style may also be used.User input to the dual-mode mobile communication device 910 is furtherenhanced with a plurality of auxiliary I/O devices 928, which mayinclude a thumbwheel input device, a touchpad, a variety of switches, arocker input switch, etc. The composed data items input by the user maythen be transmitted over the communication network 919 via thetransceiver 911.

[0075] When the dual-mode mobile communication device 910 is operatingin a voice communication mode, the overall operation of the dual-modemobile communication device 910 is substantially similar to the datamode, except that received signals are preferably output to the speaker934 and voice signals for transmission are generated by a microphone936. Alternative voice or audio I/O subsystems, such as a voice messagerecording subsystem, may also be implemented on the dual-mode mobilecommunication device 910. Although voice or audio signal output ispreferably accomplished primarily through the speaker 934, the display922 may also be used to provide an indication of the identity of acalling party, the duration of a voice call, or other voice call relatedinformation. For example, the microprocessor 938, in conjunction withthe voice communication module and the operating system software, maydetect the caller identification information of an incoming voice calland display it on the display 922.

[0076] A short-range communications subsystem 940 is also included inthe dual-mode mobile communication device 910. For example, theshort-range communications subsystem 940 may include an infrared deviceand associated circuits and components, or a short-range wirelesscommunication module such as a Bluetooth module or an 802.11 module toprovide for communication with similarly-enabled systems and devices.Those skilled in the art will appreciate that “Bluetooth”™ and 802.11refer to sets of specifications, available from the Institute ofElectrical and Electronics Engineers (IEEE), relating to wirelesspersonal area networks and wireless LANs, respectively.

[0077] The example used in the above description for the identificationinformation exchanged by mobile stations comprised IP addresses;however, other types of identification information may also beexchanged, including addresses used by networks other than the Internet.

[0078] Also, an example of a the mobile station used in this descriptionwas a dual-mode communication devices; however, the mobile stations mayalso be other types of devices, including mobile telephones, PDAs andlaptop computers which include wireless communication cards.

[0079] The structural arrangements and steps described herein and shownin the drawings are examples of structures, systems, or methods havingelements or steps corresponding to the elements or steps of theinvention recited in the claims. This written description and drawingsmay enable those skilled in the art to make and use embodiments havingalternative elements or steps that likewise correspond to the elementsor steps of the invention recited in the claims. The intended scope ofthe invention thus includes other structures, systems, or methods thatdo not differ from the literal language of the claims, and furtherincludes other structures, systems, or methods with insubstantialdifferences from the literal language of the claims.

We claim:
 1. A method of operating comprising the following steps:detecting when a first network identification code associated with afirst mobile device has changed; sending a first message via a wirelessnetwork to a first service gateway for forwarding by the service gatewayto a second mobile station wherein the first message comprises the firstnetwork identification code; receiving from a second service gateway viathe wireless network a second forwarded message that was sent by thesecond mobile station wherein the second message comprises a secondnetwork identification code that is associated with the second mobilestation; storing the second network identification code; and requestinga communication link between the first mobile station and the secondmobile station via the wireless network using the second networkidentification code wherein the communication link does not traverse thefirst or second service gateway.
 2. The method of claim 1 wherein firstservice gateway is the same physical device as the second servicegateway.
 3. The method of claim 1 wherein the first service gateway andthe second service gateway comprise an email gateway.
 4. The method ofclaim 3 wherein the first message and the second message comprise emailmessages.
 5. The method of claim 1 wherein the first service gateway andthe second service gateway comprise a short messaging service center(SMSC).
 6. The method of claim 5 wherein the first message and thesecond message comprise short messaging service (SMS) messages.
 7. Themethod of claim 1 wherein the first service gateway and the secondservice gateway comprise an internet gateway.
 8. The method of claim 7wherein the internet gateway provides a connection to an IP addressservice.
 9. The method of claim 7 wherein the first message and thesecond message comprise HTTP packets.
 10. The method of claim 9 whereinthe first mobile station queries the IP address service to determine theIP address for another mobile station.
 11. The method of claim 9 whereinthe IP address service notifies the first mobile station when the IPaddress for another mobile station has changed.
 12. The method of claim1 wherein the first service gateway is selected from a group comprisingan email gateway, a SMSC, a SMSC with an IP address exchange service,and an Internet gateway with an IP address service.
 13. The method ofclaim 12 wherein the second service gateway is selected from a groupcomprising an email gateway, a SMSC, a SMSC with an IP address exchangeservice, and an Internet gateway with an IP address service.
 14. Themethod of claim 13 wherein the second service gateway is the same typeof service gateway as the first service gateway.
 15. The method of claim13 wherein the second service gateway is a different type of servicegateway than the first service gateway.
 16. The method of claim 1wherein the first mobile station selects as the first service gateway aservice gateway from a group comprising an email gateway, a SMSC, a SMSCwith an IP address exchange service, and an Internet gateway with an IPaddress service.
 17. The method of claim 16 wherein the first mobilestation selects one service gateway type for sending the firstidentification code to the second mobile station and selects a differentservice gateway type for sending the first identification code to athird mobile station.
 18. The method of claim 16 wherein the firstmobile station selects a first service gateway type for sending thefirst identification code to the second mobile station and selects adifferent service gateway type for re-sending the first identificationcode to the second mobile station.
 19. The method of claim 1 wherein themessage type for the first message is selected from a group comprisingan email message, a SMS message, and a HTTP message.
 20. The method ofclaim 19 wherein the message type for the second message is selectedfrom a group comprising an email message, a SMS message, and a HTTPmessage.
 21. The method of claim 20 wherein the message type for thesecond message is different from the message type for the first message.22. The method of claim 20 wherein the message type for the secondmessage is the same as the message type for the first message.
 23. Themethod of claim 1 wherein the first mobile station selects the messagetype for the first message from a group comprising an email message, aSMS message, and a HTTP message.
 24. The method of claim 23 wherein thefirst mobile station selects one message type for sending the firstidentification code to the second mobile station and selects a differentmessage type for sending the first identification code to a third mobilestation.
 25. The method of claim 23 wherein the first mobile stationselects a first message type for sending the first identification codeto the second mobile station and selects a different message type forre-sending the first identification code to the second mobile station.26. The method of claim 1 wherein the first network identification codeand the second network identification code comprise IP addressesassigned by the wireless network.
 27. The method of claim 26 wherein thefirst mobile station comprises an IP-monitoring agent for detecting whenthe IP address of the first mobile station changes.
 28. The method ofclaim 27 wherein the IP-monitoring agent sends the first message afterit detects that the IP address of the first mobile station has changed.29. The method of claim 1 wherein the first message is sent in responseto a command by the user of first mobile device to send the firstmessage.
 30. The method of claim 1 wherein the first message furthercomprises status information, location information, or both status andlocation information.
 31. The method of claim 1 wherein the secondmobile station is registered as an associate of the first mobilestation.
 32. The method of claim 31 wherein the registration of thesecond mobile station is recorded in a mapping table.
 33. The method ofclaim 32 wherein the registration of the second mobile station isrecorded in a mapping table that resides in the first mobile station.34. The method of claim 32 wherein the registration of the second mobilestation is recorded in a mapping table that is external to the firstmobile station.
 35. The method of claim 32 wherein the mapping tablecomprises email addresses of associates of the first mobile station. 36.The method of claim 32 wherein the mapping table comprises SMS addressesof associates of the first mobile station.
 37. The method of claim 1further comprising the step of sending a response message to the secondmobile station in response to receiving the second message.
 38. Themethod of claim 1 wherein the communication link is a peer-to-peercommunication link.
 39. The method of claim 1 wherein the communicationlink provides a communication channel for an instant messagingconversation.
 40. The method of claim 1 wherein the communication linkprovides a communication channel for a web server to provide web pagesfor information exchange.
 41. A method in a wireless network systemhaving a first wireless base station for providing a first communicationlink to a first mobile station, a second wireless base station forproviding a second communication link to a second mobile station, andaccess to one or more service gateways for providing a message exchangeservice for the first and second mobile stations, the method comprisingthe following steps: providing a first network identification code tothe first mobile station; providing a second network identification codeto the second mobile station; transferring a first message from thefirst mobile station to a second mobile station via a first servicegateway wherein the first message comprises the first networkidentification code; transferring a second message from the secondmobile station to the first mobile station via a second service gatewaywherein the second message comprises the second network identificationcode; and providing a communication path between the first mobilestation and the second mobile station in response to a request fromeither the first or second mobile stations or both that includes thefirst and second network identification codes wherein the communicationpath does not traverse the first or second service gateway.
 42. Themethod of claim 41 wherein first service gateway is the same physicaldevice as the second service gateway.
 43. The method of claim 41 whereinthe first service gateway and the second service gateway comprise anemail gateway.
 44. The method of claim 43 wherein the first message andthe second message comprise email messages.
 45. The method of claim 41wherein the first service gateway and the second service gatewaycomprise a short messaging service center (SMSC).
 46. The method ofclaim 45 wherein the first message and the second message comprise shortmessaging service (SMS) messages
 47. The method of claim 45 wherein atleast one of the first service gateway and the second service gatewayfurther comprises an IP address exchange service.
 48. The method ofclaim 41 wherein the first network identification code and the secondnetwork identification code comprise IP addresses assigned by thewireless network.
 49. The method of claim 41 wherein the first messagefurther comprises status information, location information, or bothstatus and location information.
 50. The method of claim 41 wherein thefirst message further comprises information relating to the capabilitiesof the mobile station.
 51. The method of claim 50 wherein theinformation relating to the capabilities of the mobile station comprisesinformation that identifies a device type, one or more supportedfeatures, one or more communication methods, or any combination of oneor more device types, supported features and/or communication methods.52. The method of claim 41 further comprising the step of sending aresponse message to the second mobile station in response to receivingthe second message.
 53. The method of claim 41 wherein the communicationpath is a peer-to-peer communication path.
 54. The method of claim 41wherein the communication path provides a communication channel for aninstant messaging conversation.
 55. The method of claim 41 wherein thecommunication path provides a communication channel for a web server toprovide web pages for information exchange.
 56. A method in a firstmobile station comprising the following steps: exchanging networkidentification information with a second mobile station using a wirelessnetwork and a service gateway; storing a network identification code ofthe second mobile station; and requesting a wireless communication linkbetween the first mobile station and the second mobile station via thewireless network using the network identification code wherein thecommunication link does not require any service gateway.
 57. The methodof claim 56 wherein the service gateway comprises an email gateway. 58.The method of claim 56 wherein the service gateway comprises a shortmessaging service center (SMSC).
 59. The method of claim 56 wherein theservice gateway comprises an internet gateway.
 60. The method of claim59 wherein the internet gateway provides a connection to an IP addressservice.
 61. The method of claim 60 wherein the first mobile stationqueries the IP address service to determine the IP address for anothermobile station.
 62. The method of claim 60 wherein the IP addressservice notifies the first mobile station when the IP address foranother mobile station has changed.
 63. The method of claim 56 whereinthe service gateway is selected from a group comprising an emailgateway, a SMSC, a SMSC with an IP address exchange service, and anInternet gateway with an IP address service.
 64. The method of claim 56wherein the first mobile station exchanges identification informationwith the second mobile station using a first and a second servicegateway and wherein the first service gateway is the same type ofservice gateway as the second service gateway.
 65. The method of claim56 wherein the first mobile station exchanges identification informationwith the second mobile station using a first and a second servicegateway and wherein the first service gateway is a different type ofservice gateway than the second service gateway.
 66. The method of claim56 wherein the first mobile station exchanges identification informationwith the second mobile station using a first and a second servicegateway
 67. The method of claim 66 wherein the first mobile stationselects as the first service gateway a service gateway from a groupcomprising an email gateway, a SMSC, a SMSC with an IP address exchangeservice, and an Internet gateway with an IP address service.
 68. Themethod of claim 67 wherein the first mobile station selects one servicegateway type for sending identification information to the second mobilestation and selects a different service gateway type for sending theidentification information to a third mobile station.
 69. The method ofclaim 67 wherein the first mobile station selects a first servicegateway type for sending identification information to the second mobilestation and selects a different service gateway type for re-sending theidentification information to the second mobile station.
 70. The methodof claim 56 wherein the identification information comprises an IPaddress assigned by the wireless network.
 71. The method of claim 70wherein the first mobile station comprises an IP-monitoring agent fordetecting when the IP address of the first mobile station changes. 72.The method of claim 56 wherein the second mobile station is registeredas an associate of the first mobile station.
 73. The method of claim 72wherein the registration of the second mobile station is recorded in amapping table.
 74. The method of claim 73 wherein the registration ofthe second mobile station is recorded in a mapping table that resides inthe first mobile station.
 75. The method of claim 73 wherein theregistration of the second mobile station is recorded in a mapping tablethat is external to the first mobile station.
 76. The method of claim 73wherein the mapping table comprises email addresses of associates of thefirst mobile station.
 77. The method of claim 73 wherein the mappingtable comprises SMS addresses of associates of the first mobile station.78. A method in a wireless network comprising the following steps:providing a first network identification code to a first mobile stationand a second network identification code to a second mobile station;transferring messages between the first mobile station and the secondmobile station via a service gateway wherein the messages comprise thefirst network identification code, the second network identificationcode, or both; and providing a communication link between the firstmobile station and the second mobile station in response to a requestfrom either the first or second mobile stations or both that includesthe first and second network identification codes wherein thecommunication link does not require any service gateway.
 79. The methodof claim 78 wherein the service gateway comprises an email gateway. 80.The method of claim 79 wherein the messages comprise email messages. 81.The method of claim 78 wherein the service gateway comprises a shortmessaging service center (SMSC).
 82. The method of claim 81 wherein themessages comprise short messaging service (SMS) messages.
 83. The methodof claim 81 wherein the service gateway further comprises an IP addressexchange service.
 84. The method of claim 78 wherein the first networkidentification code and the second network identification code compriseIP addresses assigned by the wireless network.
 85. The method of claim78 wherein the messages further comprise status information, locationinformation, or both status and location information.
 86. A mobilestation comprising: a wireless transceiver for communicating over awireless network; a user interface; a memory module that comprisesstorage space for an identification code assigned by the wirelessnetwork to the mobile station and storage space for an address mappingtable that can be used to store the identification codes of other mobilestations; and an address application, the address application beingoperative to send outgoing identification code messages to the othermobile stations listed in the address mapping table, the outgoingidentification code messages including the identification code assignedby the network to the mobile station.
 87. The mobile station of claim 86wherein the identification code is an IP address.
 88. The mobile stationof claim 86 further comprising a message application for receiving anidentification message from the wireless network that includes theidentification code for the mobile station and for storing thatidentification code in the memory module.
 89. The mobile station ofclaim 86 wherein the address application is operative to populate theaddress mapping table with identification codes for other mobilestations from messages received from the other mobile stations.
 90. Themobile station of claim 86 wherein the mobile station is operative tosend the identification code assigned to the mobile station in anoutgoing identification code message of a message type selected from agroup comprising an email message, a SMS message, and a HTTP message.91. The mobile station of claim 90 wherein the mobile station isoperative to receive an identification code from a second mobile stationfrom an incoming identification code message of a message type selectedfrom a group comprising an email message, a SMS message, and a HTTPmessage.
 92. The mobile station of claim 91 wherein the message type forthe outgoing identification code message is different from the messagetype for the incoming identification code message.
 93. The mobilestation of claim 91 wherein the message type for the outgoingidentification code message is the same as the message type for theincoming identification code message.
 94. The mobile station of claim 91wherein the first mobile station selects one message type for sendingthe outgoing identification code message to the second mobile stationand selects a different message type for sending the outgoingidentification code message to a third mobile station.
 95. The mobilestation of claim 91 wherein the first mobile station selects a firstmessage type for sending the outgoing identification code message to thesecond mobile station and selects a different message type forre-sending the outgoing identification code message to the second mobilestation.